Dynamic Tree Path Sum

Problem Statement

Dynamic Tree Path Sum Problem Description You are given a rooted tree consisting of n nodes. The nodes are numbered 1, 2, ..., n , and node 1 is the root. Each node has a value. Your task is to process following types of queries: change the value of node s to x calculate the sum of values on the path from the root to node s Input The first input line contains two integers n and q : the number of nodes and queries. The nodes are numbered 1, 2, ..., n . The next line has n integers v1, v2, ..., vn : the value of each node. Then there are n - 1 lines describing the edges. Each line contains two integers a and b : there is an edge between nodes a and b . Finally, there are q lines describing the queries. Each query is either of the form "1 s x" or "2 s". Output Print the answer to each query of type 2. Constraints 1 ≤ n, q ≤ 2 ċ 10 5 1 ≤ a, b, s ≤ n 1 ≤ v i , x ≤ 10 9 Examples Example 1: Input: 5 3 4 5 2 1 2 1 2 1 3 3 4 3 5 2 4 Output: 11 8